[Stevejbc]

Hello

Long time reader first time posting. Been screening for over 7 years and just recently we have been having issues of after coating our screens some of them will have what looks like water drips running down them. This is happening with 2 different types of emulsions.
After final degreasing we will stack side by side and dry with a fan blowing on the screen. This time it was over the weekend and just coated them and some have this streaking issue???
Thin side of the coater 1 coat backside 1 coat inside.

Any ideas?

I have a picture but not sure how to upload it??

 

[Sulp]

Are you flood rinsing after degreasing? Very important. Its not the emulsion at all. What is most likely happening is that surfactants and chemicals are dripping off of the metal and running down the mesh while its drying. And when that happens it's gonna screw up your coat and cause problems. Once you are done degreasing take a regular hose (not pressure washer) and staring at the top of the metal rinse the entire screen from top to bottom being careful not to splash anything back up onto the screen. It removes all that residual chemical and will eliminate the drip marks.

also, your coating technique is going to leave you with a low EOM (emulsion over mesh) and will exaggerate your issues. At minimum do 1 on squeegee side, 1 on shirt side, and 1 more on the squeegee side. And on lower mesh (83, 110, 137) finish with 2 or 3 passes on the squeegee side. It will make your screens and stencil so much better.

 

[htorez]

well, whenever we going to reply or give a post, bellow text option box there bellow has another box, from that box we can see manage attachment option that's the right place!

 

[Stevejbc]

Sulp
Thank you and that makes a lot of sense. We do rinse with a hose after degreasing but I dont think we do it enough. Im sure thats going to be the issue because its not happening to all the screens.

htorez
I dont have a manage attachment box on my view. I have misc. options, fancy media options, thread subscription and rate thread.
Would you know why?

 

[htorez]

Hello

Long time reader first time posting. Been screening for over 7 years and just recently we have been having issues of after coating our screens some of them will have what looks like water drips running down them. This is happening with 2 different types of emulsions.
After final degreasing we will stack side by side and dry with a fan blowing on the screen. This time it was over the weekend and just coated them and some have this streaking issue???
Thin side of the coater 1 coat backside 1 coat inside.

Any ideas?

I have a picture but not sure how to upload it??

well, you can do!